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unlockpt(3p) — Linux manual page

UNLOCKPT(3P)            POSIX Programmer's ManualUNLOCKPT(3P)

PROLOG        top

       This manual page is part of the POSIX Programmer's Manual.  The       Linux implementation of this interface may differ (consult the       corresponding Linux manual page for details of Linux behavior), or       the interface may not be implemented on Linux.

NAME        top

       unlockpt — unlock a pseudo-terminal master/slave pair

SYNOPSIS        top

       #include <stdlib.h>       int unlockpt(intfildes);

DESCRIPTION        top

       Theunlockpt() function shall unlock the slave pseudo-terminal       device associated with the master to whichfildes refers.       Conforming applications shall ensure that they callunlockpt()       before opening the slave side of a pseudo-terminal device.

RETURN VALUE        top

       Upon successful completion,unlockpt() shall return 0. Otherwise,       it shall return -1 and seterrno to indicate the error.

ERRORS        top

       Theunlockpt() function may fail if:EBADFThefildes argument is not a file descriptor open for              writing.EINVALThefildes argument is not associated with a master pseudo-              terminal device.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       See the RATIONALE section forposix_openpt(3p).

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

grantpt(3p),open(3p),posix_openpt(3p),ptsname(3p)       The Base Definitions volume of POSIX.1‐2017,stdlib.h(0p)

COPYRIGHT        top

       Portions of this text are reprinted and reproduced in electronic       form from IEEE Std 1003.1-2017, Standard for Information       Technology -- Portable Operating System Interface (POSIX), The       Open Group Base Specifications Issue 7, 2018 Edition, Copyright       (C) 2018 by the Institute of Electrical and Electronics Engineers,       Inc and The Open Group.  In the event of any discrepancy between       this version and the original IEEE and The Open Group Standard,       the original IEEE and The Open Group Standard is the referee       document. The original Standard can be obtained online athttp://www.opengroup.org/unix/online.html .       Any typographical or formatting errors that appear in this page       are most likely to have been introduced during the conversion of       the source files to man page format. To report such errors, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017UNLOCKPT(3P)

Pages that refer to this page:stdlib.h(0p), grantpt(3p), open(3p), posix_openpt(3p), ptsname(3p)

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